Apparatus and process for continuously removing volatile matter from a liquid



A. U. AYRES ET AL APPARATUS AND PROCESS FOR CONTINUOUSLY REMOVING VOLATILE MATTER FROMA LIQUID Filed March 29, 1934 m m S m m V Y m mom uso 3 m H T R A N mg mm Bmswleg,

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Patented Jan. 26, 1937- APPARATUS AND PROCESS FOR OUSLY REMOVING VOLATILE MATTER FROM A mourn Arthur U. Ayres, Chestnut Hill, and Nathaniel Brewer, Lansd owne, Pa., assignors to The Sharples Specialty Company, Philadelphiajl'a'. Application March 29, 1934, Serial No. 717,882 10 Claims. ((1159-44) This invention relates to the 'art of purifying liquids and was conceived as the solution of problems encountered incident to the continuous refining of fatty oilsby a process invented by Edward M. James and described in co-pendi'ng applications Serial Nos. 567,220 'and 659,918, filed on October 6, 1931, and March 7, 1933, respectively. While the present invention is adapted for use in connection with other processes'than that defined in these James applications, the nature of the problem presented and of its, solution will be better understood by reference to that process.

In accordance with th'method described in the above identified James applications, a fatty oil and alkali are continuously fed in carefully proportioned amounts through a continuous high speed mixing device adapted to effect an intimate contact therebetween', and the mixture of oil and soap-stock formed by the reaction in the mixing device is continuously passed from that mixing device through a continuous heater which rapidly raises the mixture to a temperature which facilitates centrifugal separation of the soap-stock from the neutral oil. The mixture is then passed directly from the heater to a primary battery of centrifugal separators for separating soap-stock from the oil. 7 Such a method of operation possesses impor- 30 tant advantages from the standpoint of avoidance of loss of valuable oil by saponification and entrainment in the soap stock and it effects considerable economies in time, space and equipment. Purified oil passing from this primary purifying system, like purified oil obtained by the more conventional gravity settling process, contains, however, a certain amount of impurities in the nature of aqueous alkali solution and soap-stock. vThese impurities tend to cause a saponification of the purified oil when they are allowed to remain in contact with it for a prolonged length of time and it is accordingly desirable that they be removed so promptly that deteriorating effects caused by their presence are arrested before substantial damage to the oil has occurred.

To this end the oil discharged from the primary centrifugal separators .is passed promptly through apparatus adapted to eflect a continuous washing of theoil with warm water. In order to complete the removal of the impurities as promptly as possible, the major portion of the wash water and impurities is then continuously separated from the oil by a secondary battery of centrifugal separators.

In the practice of such a process, the oil discharged from the secondary battery of centrifuges is still contaminated with a small quantity of water and other volatile impurities and such impurities cause deterioration of the oil unless promptly removed. The principal object of the present invention has been to provide a method and apparatus by which the removal of these impurities may be rapidly eifected in the treatment of oil discharged from a system of this general type.

In'connection with a system of this character, the rate of flow of oil through the system is necessarily variable, these variations in fiow being due to the curtailment of use of one or more of the centrifuges of the primary or sec ondarypurifying system, or variations in the rate of output with respect to one or more of the centrifuges, and being necessitated by re quirements of bowl cleaning, variations in character of the oil under treatment, variations in I supply or other factors. Since it is important sonably accurately co-ordinated with the rate of discharge from the secondary purifying system.

In the form of evaporating apparatus used, the oil or other liquid under treatment is injected in dispersed form through a plurality of nozzles or'the like. It is desirable, as described above, that the rate of injection of oil into this apparatus be co-ordinated with the rate of supply of oil from the purifying system. Such co-ordination presents a difflcult problem, however, under conditions of'curtaileddischarge, for substantial curtailment of discharge through a nozzle results in a failure to obtain adequate dispersion incident to such discharge and accordingly results in loss of efficiency in the evaporating operation. A further feature of the invention consists in the avoidance of this difilculty by the use of a plurality of parallel dis-' charge outlets each of which is adapted to discharge liquid'into the evaporating chamber in dispersed form, and in the control of such parallel discharge outlets in such a, manner as to entirely suspend the injection of liquid through one or more of themupon curtailment oi the rate of supply. By operating the system in this manner, it is possible to maintain a substantial volume of discharge through each nozzle through which discharge is taking place during any given stage of the operation, and curtailment of the rate of discharge of the oil from the secondary centrifuges, for example, does not result in the above mentioned dimculties of inin inadequately dispersed form. T

A further feature of the invention consistsin an arrangement whereby'liquid is discharged into an evaporating chamber through a plurality of The invention will be better understood by reference to the attached drawing whenlconsider'ed in connection with the following detailed description.

In .thedrawing, the singleflgure is a diagram .matic side elevation of apparatus illustrating the features of the invention. e

Referring to the drawing by reference characters, the numeral l0 indicates a centrifugal separator which may be one of a battery of separators adapted to discharge a liquid which has been subject to treatment and which contains undesired I volatile impurities.

Such liquid may, for example, comprise a fatty oilpurified by the James process described above and containing a small amount of residual moisture. The liquid discharged from the purifying system is fed indirectly, as described hereinafter, to an evaporating chamber H, which may be connected with a vacuum pump or other suitable evacuating mechanism or apparatus. The feed of liquid to the evaporating chamber is co- -ordinated with the rate of discharge fromthe purifying system by the injection of such liquid into the evaporating chamber through a plurality of parallel discharge outlets I3 which are providedwith connections in the form of valves [4 which are adapted to be selectively closedin response to curtailment of flow of liquid from the centrifugal separators. This result is obtained by passing liquid from the centrifuges l0 into a float tank l5 which contains a heating coil l6 adapted to heat the liquid to a temperature facilitating the evaporation of volatile impurities therefrom upon injection thereof in dispersed form into the evacuated evaporating chamber.

The float tank [5 contains a float II which is connected to .a float arm 3 which successively controls a plurality'of switches ontained in a switch box l9 for effecting suc essive actuation of the valves "responsive to the level of liquid within the tank IS. A plurality of mercury con tact switches within the switch box l9 may, for example, be successively operative to effect-actuation of solenoids 20 successively controlling the operation of valves 1 4 in response to varying levels of liquid within the tank IS, the solenoids being connected with the switch. box l9 through parallel electrical connections 2i forming a part of a one of the valves I4 through the energization of jection ofliquid into the evaporating chamber.

of liquid into this chamber being caused by the vacuum within that chamber. If the rate of dis-- charge through the outlet I; which is operative at this stage of the operation is vless'than the rate of discharge from the centrifuge. ill, the level of liquidiin the float tank-l5 will continue to' rise and will cause actuation of a second'switch and associated solenoid andvalve to eflect discharge of liquid through aseco nd'discharge outlet ll.

If thefeedof liquid is s'tillinexcess of the capaci-. .ty of the two discharge outlets now open, the

and successively cause closure of one or more of the valvesl4, thereby effecting cessation of feed through one .or more discharge outlets while maintaining the feed through the remaining dis charge outlets of the series at full capacity; It

will thus be seen that the problem of correlating the rate of feed to theevaporating apparatus with the rate of discharge of liquid from the refining system or other source of supply-is solved without impairment of the efficiency of the evaporating chamber, such as would be involved if a single valve controlled the flow of liquid to the evaporating chamber by throttling, and an attempt were made to effeot'control of flow of liquid to the evaporating chamber by manual or automatic control of that valve.

In case liquid is fed to the evaporating chamber in substantial excess of its discharge capacity, the float switch 23, will be actuated to open the circuit 22 incorporating the three parallel branches 2! and consequently cause de-energization of all of the solenoids 20 and suspension of flow through every one of the discharge outlets l3. This suspension of flow will continue until the level of liquid in the evaporating chamber has dropped to a sufficient extent to render resumption of flow to the evaporating chamber desirable. v v I Modifications will be obvious to thoseskilled in the art and we do not therefore wish to be limited except by the scope of the sub-joined claims. While the specific form of the invention described above involves selectively controlling the-number of discharge outlets in response to reduced rate of flow of liquid to the evaporating chamber, a partially analogous result may be attained by accumulating a reserve body of liquid and passing the liquid to the evaporating apparatus, at substantial capacity at alternating periods of feed, the feed being entirely suspended between such alternating feed periods. In connection with such a system of operation, the duration of the successive periods of feed and of the periods of cessation of feed would naturally be determined by the rate of supply of liquid to the evaporating apparatus. It will thus be seen that the most important feature of the invention con sists in the feed of liquid through the discharge nozzle or nozzles which are operative at any given stage of the practice of the invention at substantial capacity and that alternative methods of accomplishing this result fall within the spirit of the invention. 1

We claim: 1. In apparatus for continuously removing volatile impurities from a liquid, the combination comprising a dehydrating chamber, a supply tank, means for conducting liquid from said supply tank to said dehydrating chamber, plural controlled by the parallel means for injecting liquid into said dehydrating chamber in dispersed form, and means level of liquid in said supply tank for causing discontinuance of injector of liquid through one or more of said injecting means selectively. h 2. In apparatus for continuously removing volatile impurities from a liquid, the combination comprising a dehydrating chamber, a supply tank, means for conducting liquid irom said supply tank to said dehydrating chamber, plural parallel means for injecting liquid into said dehydrating chamber in dispersed form, means controlled by the level of liquid in said supply tank for causing discontinuance of injection of liquid through one or more of said injecting means selectively and means for causing discontinuance oi injection of liquid through all of said injecting means upon feed of liquid to said dehydrating chamber in substantial excess of its operating capacity.

3. An evaporating. apparatus for removing residual volatile impurities from a liquid supplied at a variable rate comprising an accumulating tank, means for feeding said liquid continuously from said accumulating tank to an evaporating chamber and including means for injecting liquid into the evaporating chamber in dispersed form through a plurality of parallel discharge outlets, valve means for causing discontinuance of the discharge of liquid through one or more of said outlets selectively, means operative in response to diminution in the rate 01' supply of said liquid. to the accumulating tank for actuating said valve means to closed position, whereby to maintain substantial volume of discharge through the outlets with respect to which the discharge is not so discontinued.

4. An evaporating apparatus for removing residual volatileimpurities from a liquid supplied at a variable rate comprising an accumulating tank, means for feeding said liquid continuously from said accumulating tank to an evaporating chamber, said means including means for injecting the liquid into the evaporating apparatus in dispersed form through a plurality of parallel discharge outlets, and means for causing discontinuance of the discharge of liquid through one or more level of liquid in said accumulating tank, whereby to maintain a suflicient volume of discharge through the outlets with respect to which the discharge isnot so discontinued to insure a high degree oi dispersion of said liquid.

5. The method of continuously removing volatile impurities from aliquid continuously supplied at a variable rate which comprises subjecting such liquid to a continuous evaporating operation while discharging such liquid continuously in dispersed form at a plurality of parallel discharge points and interrupting the discharge through one or more of said discharge points selectively to maintain the number of discharge points operating at any given stage of operation approximately proportionate to the rate of supply of said liquid.

6. In apparatus for continuously removing volatile impurities from a liquid, the combination comprising a dehydrating chamber, means for conducting liquid tosaid dehydrating chamber, plural parallel means for injecting liquid into said dehydrating chamber in dispersed form and means for causing discontinuance of injection of liquid through one or more of said injecting of said outlets selectively in response tov the operation of a float valve controlled by the means selectively in response to diminution in rate of supply of said liquid to the purifying apparatus, whereby to comprising a dehydrating chamber, means for I conducting liquid to said dehydrating chamber, a plurality of parallel discharge nozzles interconmaintain a substantial volume of discharge suflicient to effect a high degree nected with said conducting means and projesta ing into said dehydrating chamber and adapted to effect injection of liquidinto said dehydrating chamber in. dispersed form, and means for caus ing discontinuance of injection of liquid through one or more of said discharge nozzles selectively in response to diminution in rate of supply of said liquid to the purifying apparatus, whereby to maintain a volume of discharge suflicient to effect a high degree of dispersion through each of the discharge nozzles through which discharge is not so discontinued.

8. In apparatus for continuously removing volatile impurities from a liquid, the combination comprising a dehydrating chamber, means for supplying liquid at a variable rate, means for conducting liquid to said dehydrating chamber, plural parallel means for injecting liquid into said dehydrating chamber in dispersed form, and means controlled by the rate of supply for causing discontinuance of injection of liquid through one or more of said injecting means selectively in response to diminution in rate of supply of said liquid to the purifying apparatus, whereby to maintain a volume of discharge sufficient to effect a high degree of dispersion through each of the injecting means through which discharge is not so discontinued.

9. In apparatus for continuously removing volatile impurities from a liquid supplied at a variable rate, the combination comprising a hydrating chamber, a conduit through which liquid is fed to said dehydrating chamber, plural parallel means for injecting liquid into said dehydrating chamber actuated in response to diminution in the rate of supply for causing discontinuance of injection of liquid through means selectively, whereby to maintain a substantial volume of discharge and dispersion through each of the injecting means through which discharge is not so discontinued, and means for suspending injection of liquid through all of said injecting means upon feed of liquid to saiddehydrating chamber in substantial excess of its operating capacity.

10. In apparatus .for continuously removing volatile impurities from a liquid supplied at a variable rate, the combination comprising a dehydrating chamber, a conduit through which liquid is fed to said dehydrating chamber, plural parallel means for injecting liquid into said dehydrating chamber in dispersed form, a valve associated with each' of said injecting means adapted selectively to permit or prevent injection of liquid into said dehydrating chamber through the injecting means controlled thereby, and electrical control means for suspending feed of liquid through one or more of said valves selectively in one or more of said injectingin dispersed form, means CERTIFICATE OF CORRECTION.

Patent NO; 2,068,971. v Januaryihe'p1193121 ARTHUR u.- AYRES, ET in;

It is hereby certified that error appears innthe printed speciiicaticxif or the "above numbered patent requiring correction as follows: Page; 3,1"

first column, line 4, claim 1 for "inj ector" read injection; and that the said Letters Patent should be readwith this correction therein that the same may congorm to the record of the case in the Patent- Office. Signed and sealed this 20th day of April, A. D. 1937.

' o Henry Van Arsdale (Seal). Acting Commissioner ct. Petm itl. 

